While there has been much publicity about the poisoning effects of ecstasy, following events such as the death of 18-year-old Leah Betts, the long- term dangers have largely been ignored.
But Professor Richard Green, from the Astra Neuroscience Research Unit in London, and Professor Guy Goodwin, of the MRC Brain Metabolism Unit, Royal Edinburgh Hospital, believe the drug's permanent psychiatric effects are potentially more damaging than its toxicity.
The drug, otherwise known as MDMA, produces a euphoric rush with feelings of exhilaration and the ability to dance for hours. The downside is that body temperature can rise extensively, leading to heatstroke, convulsions and death.
An estimated 500,000 people take ecstasy in Britain every week but only a small number of people have died - about 50 in Britain since the late 1980s.
The Home Office believes that10 per cent of 14 to 19-year-olds have experimented with the drug.
The question of long-term damage from using ecstasy has been a controversial one. But experiments with laboratory rodents and monkeys have shown that mild doses of the drug caused long-term destruction of nerve cells in the brain concerned with the release of a mood-altering chemical, serotonin. Even when the destroyed nerve cells regrew, they did so in an abnormal way.
"No unequivocal evidence yet exists that regular users of ecstasy have brain damage but the studies that have been performed give no grounds for reassurance", the professors said.
One study found that 30 regular users of ecstasy have lower concentrations of serotonin in brain spinal fluid, similar to the effects seen in monkeys.
Another study in the US, carried out for the Food and Drug Administration on 18 human volunteers who had taken the drug before, found "profound" and "permanent" effects on the brain which were confirmed by brain scans on long-term users.
Since serotonin played a major part in mood control, regular ecstasy users might be expected to have psychiatric problems - and there were case reports to support this.
"What is of great concern is the possibility that the neurotoxicity in humans might be slow and insidious, and that problems such as major depression will appear only in several years' time." The authors added. "A recent editorial argued against legalising ecstasy because of the problems of acute toxicity. To this we add that no one should seriously consider legalising a compound that can be shown to cause long-term neurodegeneration in rodents and primates at doses that differ little from those used recreationally by humans."Reuse content